1H-Pyrazolo[1,5-b][1,2,4]triazole magenta couplers are disclosed in JP-A-59-171956 (corresponding to U.S. Pat. No. 4,621,046) (the terms "JP-A" as used herein means an "unexamined published Japanese patent application") and U.S. Pat. No. 4,540,654. It is known that these couplers are excellent in color reproducibility and are preferred from the viewpoint of synthesis. It is also known that the couplers give a dye image having excellent fastness when used together with certain kinds of anti-fading agents. JP-A-1-302249 (corresponding to U.S. Pat. No. 4,882,266) discloses couplers which give a dye image having further improved fastness. Namely, the couplers are 1H-pyrazolo[1,5-b][1,2,4]triazole magenta couplers having a tertiary alkyl group at the position-6 and a phenylene group at the position-2. Dye images formed from these couplers have high fastness to light and heat. The concretely exemplified compounds of the couplers described in U.S. Pat. No. 4,882,266 are couplers wherein the phenylene group at the position-2 has a sulfonamido group at the meta-position. It has been found that dyes obtained from couplers wherein the phenylene group at the position-2 has a substituent group at the meta-position have spectral absorption characteristics. Namely, absorption on the foot of the long wavelength side is large and broadened. Accordingly, a further improvement has been demanded from the viewpoint of color reproducibility.
Further, it has been found that light-sensitive materials containing these couplers have a problem in that the photographic performance thereof is changed during the course of storage, until development, after exposure.
Furthermore, there has been a demand to provide light-sensitive materials which are scarcely changed in photographic characteristics by a change in the composition of a processing solution in development. Changes in the composition of processing solutions are mainly caused by (1) an increase in the mixing and accumulation of the ingredients of other processing solutions in running processing or (2) intermittently continuous processing conducted using automatic processors. This phenomenon is remarkable when the replenishment rates of the processing solutions are reduced and the ratios of tank solutions refreshed by replenishers are lowered or when the use of the processing solutions is prolonged. The above description "the mixing of the ingredients of other processing solutions" is caused by the splash of an adjoining processing solution during processing, or back contamination which is a phenomenon wherein ingredients in the processing solutions immediately after development are brought into a color developing solution by a conveying leader or belt or hangers which hang films. When the light-sensitive materials containing couplers described in U.S. Pat. No. 4,882,266 are processed with a color developing solution containing fixing agents in a contaminant amount by the ingredients becomming mixed and accumulated, photographic characteristics are greatly changed. Hence, a further improvement has been demanded.
Further, light-sensitive materials containing couplers wherein a phenylene group at the position-2 has a methyl group at the ortho-position as described in JP-A-3-48845 have a problem in that color developability is low in addition to the above-described problem. Accordingly, a further improvement has been demanded.